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Mars NASA Space Science

NASA Rover May Contaminate Its Samples of Mars 147

Posted by Soulskill
from the no-problem-just-launch-another-one dept.
sciencehabit writes "The Curiosity rover will definitely find evidence of an advanced civilization if it lands safely on Mars. That's because rock samples the rover drills are likely to be contaminated with bits of Teflon from the rover's machinery, NASA announced during a press teleconference. The bits of Teflon can then mix with the sample, which will be vaporized for analysis. The problem for the scientists is that Teflon is two-thirds carbon — the same element they are looking for on Mars." Fortunately, this problem isn't a showstopper: "...there are still mitigation steps to take if SAM's analysis is potentially compromised. Contaminant production appears to be stronger in the drill's percussion mode, when it pounds powerfully and rapidly on Martian rock. So ratcheting the percussion down, or switching over to the more gentle rotary mode, may make the issue more manageable. If that doesn't work, the MSL team could just take the drill out of commission, solely scooping soil instead of also boring into rock. Curiosity could still access the interior of some Martian rocks by rolling over them with its wheels, Grotzinger said. But all in all, he's confident that the team will figure things out in the next month or two."
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NASA Rover May Contaminate Its Samples of Mars

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  • Two-thirds carbon? (Score:5, Informative)

    by jeffb (2.718) (1189693) on Tuesday June 12, 2012 @03:10PM (#40299451)

    I think somebody had another English-metric goof when they were doing their stoichiometry.

    (CF2)n -> 24% carbon, 76% fluorine by mass, at least by my calculations.

    • by vlm (69642) on Tuesday June 12, 2012 @03:26PM (#40299637)

      Actually its even worse. I'm assuming they're using a mass spectrometer and you get one C ion for every two F ions. So they got the concept of the ratio correct, but backwards. Well, its just journalism and PR, can't expect much from those folks.

      • Re: (Score:3, Informative)

        Nobody even tried this to test it out? They didn't learn from previous missions?

        I recall Voyager gathering samples, dumping it into a container, and pouring chemicals on it. Whoa! Carbon, life.

        Then someone said, well, no, probably not, there were other explanations.

        Why didn't someone say, "Presume the test is positive -- let's shoot holes in it." them iterate proving the test until there are no more holes they can think of.

        Is that so hard before you spend billions?

        • by Urban Garlic (447282) on Tuesday June 12, 2012 @04:13PM (#40300247)

          > I recall Voyager...

          Viking, and it wasn't looking for carbon, specifically, it was looking for long-chain hydrocarbons. Good link here [wikipedia.org].

        • by Solandri (704621) on Tuesday June 12, 2012 @07:21PM (#40302629)

          Why didn't someone say, "Presume the test is positive -- let's shoot holes in it." them iterate proving the test until there are no more holes they can think of.

          Is that so hard before you spend billions?

          The flip side is spending tens of millions thinking of all the possible ways the test could provide a false positive, designing them out of the test, then sending Viking to Mars and having the test come out negative. Then you get criticized or wasting all that money coming up with a test which would generate a foolproof positive result, forgetting that the result could be negative.

          Science is like filling an empty map. If you blindly concentrate all your resources in one area of the map, you could end up knowing a lot about an uninteresting place (like say, the middle of the ocean). But if you use a shotgun strategy and first spend minimal resources in lots of locations, you can see where the interesting parts of the map are and concentrate your resources on exploring those in the future.

          Viking was the first Mars lander. By no means was it planned to be the last. They put a simple experiment (along with several others) on board which would provide a quick answer to a "gee I wonder what happens if..." question. If it came back negative, oh well. Since it came back positive, then they could spend millions scrutinizing the result and planning a better test for future landers.

          • by Joce640k (829181)

            Viking was the first Mars lander. By no means was it planned to be the last.

            Viking was looking for big stuff, not microscopic traces. When Viking landed they still thought Mars might have plant life.

      • by Dthief (1700318)
        mass spec doesnt obliterate molecules into atomic constituents, it breaks it up into fragments....so you arent looking at individual C's and F's
      • Yes, but with MS they will get the Mw of the various components. It shouldn't be too hard to correct for - if it's MS.

  • Teflon (Score:5, Funny)

    by ravenspear (756059) on Tuesday June 12, 2012 @03:22PM (#40299577)

    Well, at least the samples won't get stuck.

  • by Baloroth (2370816) on Tuesday June 12, 2012 @03:23PM (#40299595)

    I don't know how sensitive the detector they are using is, but they should also be able to detect the fluorine molecules (which outnumber the carbon 2 to 1, unlike what TFA claims). I don't imagine they expect to find a lot of fluorine in the rocks on Mars, so the presence of fluorine indicates the sample is contaminated and they should ignore the carbon. If the analysis is really sensitive, they could even correlate the amount of fluorine with the expected amount of carbon (since it should be exactly 2 to 1), allowing the contaminating carbon to be eliminate from the analysis.

    This assumes the fluorine can be accurately analyzed, which may be a major issue since it is extremely reactive. I'm not a chemist, though, so I don't know how big an issue that could be.

    • by vlm (69642)

      correlate the amount of fluorine with the expected amount of carbon (since it should be exactly 2 to 1)

      The best news is that commercial teflon is pretty pure stuff inherently. There is some odd acid manufacturing byproduct but I remember it was measured in PPB so there's not much. Probably baked aerospace grade stuff is pretty ridiculously pure so that 2 to 1 ratio will hold quite well.

      This assumes the fluorine can be accurately analyzed, which may be a major issue since it is extremely reactive.

      Extremely reactive means easily ionizable means its really easy to detect in a mass spectrometer. So thats good news, assuming thats what they're doing.

      If they can heat the samples they can play games with the pyrolosis tem

  • They could have used a diamond-tipped drill.
  • Should be enough fuel for a turn around. :-)
  • by khallow (566160) on Tuesday June 12, 2012 @06:51PM (#40302321)
    We see here one of the primary strengths of robotics over human missions, namely, the speed with which one can correct errors . It'll be no more than 10 years, er, 20, no make that 30 or even... 40 years before they can get another mission up there with a drill that isn't contaminated, maybe. With a manned mission, they'd be able to troubleshoot the drill on the spot, which is clearly an inferior process.
    • by Solandri (704621)
      These landers and any probes which might impact a planet/moon are sterilized before being sent to minimize the risk of biological contamination. So yeah, having a man there to troubleshoot the drill on the spot would clearly be an inferior process.
      • by khallow (566160)

        to minimize the risk of biological contamination

        I think we're a bit at cross-purposes. I would much rather maximize the risk of biological contamination. I figure a well developed high tech society on Mars gives us the best chance of doing that.

        • It seems odd that you would criticise the robot for contaminating the environment, and then later say that you don't care about contamination, even approve of it. But then to the external observer many of the notions in support of reusing the technology of yesteryear (e.g. Horse drawn buggies, mine ponies, gas light, manned space travel) seem anachronistic and self contradictory.
          • by khallow (566160)

            It seems odd that you would criticise the robot for contaminating the environment, and then later say that you don't care about contamination

            You speak of and conflated a different sort of problem. In the current case, the contamination might render this particular drill useless for its purpose, meaning the sort of experiment it was meant to do may well be delayed till some distant time when another probe comes by this location to drill samples. While biological contamination from humans is a long term problem (a problem we've successfully dealt with here on Earth, I might add) which can be filtered out of the experiments run by the researchers.

            But then to the external observer many of the notions in support of reusing the technology of yesteryear (e.g. Horse drawn buggies, mine ponies, gas light, manned space travel) seem anachronistic and self contradictory.

            T

            • by khallow (566160)

              In that sense, it makes sense to ask if robotics is meant to replace humans, then how would it do so?

              I lost a paragraph here that noted that the tasks which we did before such as riding a horse-drawn buggy are still done today, just advanced considerably (cars, heavy and automated mining equipment, and electric light). So the question is what replaces the capabilities of humans in such a scheme. It seems to me a bit like deciding to forgo horses prior to the advent of the replacement for the horse. There might be a way to do it, but it seems to me to just be a waste of time.

              With any sort of manned space

    • by kamapuaa (555446)

      A manned mission would be so much more expensive there's no use comparing. For half the price of a manned mission, they could have sent over a few really fucking amazing general-purpose robots that could also troubleshoot the drill. Instead, they sent over a relatively small special purpose instrument, that it sounds like will be able to deal with the situation.

      • by khallow (566160)

        For half the price of a manned mission, they could have sent over a few really fucking amazing general-purpose robots that could also troubleshoot the drill.

        Half the price? That's not much of a cost savings is it?

        Instead, they sent over a relatively small special purpose instrument, that it sounds like will be able to deal with the situation.

        By not functioning as intended. They might not even use it at all. I found that part quite illuminating.

    • Since they corrected the error without any delay to the mission, your jibe seems to be a bit off target. Particularly given that the "error" is one that might conceivably have occurred and affected a single experiment.

      Compare that to the type of error that could arise using the human mission - human falls over (as they are wont to do), breaks femur. Compound fracture. How do we recover form this error, given the problem of the human lying in agony on the surface of Mars, bleeding internally and slowly dy

      • by khallow (566160)

        Since they corrected the error

        They didn't. They just went ahead with the mission. There are some compensating strategies and it may well turn out that the mission isn't seriously compromised by this alleged contamination in the first place. But this sort of thing is a huge weakness of the current approach. If they end up losing significant capabilities, they may never conduct the observations, within our lifetimes, for which the instrument was intended.

        A manned mission would have far great ability to compensate for such a problem.

      • by khallow (566160)
        As to human deaths? We can always launch more. Once we've figured out how to launch people to Mars, we can reuse the designs, perhaps the very vehicles themselves. There's plenty of skilled people too.

        We don't as in the case of the Mars Science Laboratory, design a completely new mission and do everything from scratch.
    • by Rich0 (548339)

      Yeah, but this is a robotic mission that gives good results now, compared to a hypothetical manned mission that costs 100X as much this year and every year for the next 50 years, and gives perhaps better results 50 years from now, assuming the crew doesn't die on the way.

      We could probably send 10 probes every launch window for a fraction of the cost of a manned mission. Surely they can't all have fatal flaws?

      • by khallow (566160)

        Yeah, but this is a robotic mission that gives good results now, compared to a hypothetical manned mission that costs 100X as much this year and every year for the next 50 years, and gives perhaps better results 50 years from now, assuming the crew doesn't die on the way.

        That's a hypothetically manned mission. I was refering to missions that had people on them not an activity that spends money for 50 years and might have people going to Mars at the end of the period. You know, much like the present day, even to the money spent.

        We could probably send 10 probes every launch window for a fraction of the cost of a manned mission. Surely they can't all have fatal flaws?

        And what would we do with them that would justify not having a manned presence? People keep forgetting how little we do with probes these days. It only looks like a lot because it's been 40 years since the last manned mission to another body in the So

        • by Rich0 (548339)

          Yeah, but this is a robotic mission that gives good results now, compared to a hypothetical manned mission that costs 100X as much this year and every year for the next 50 years, and gives perhaps better results 50 years from now, assuming the crew doesn't die on the way.

          That's a hypothetically manned mission. I was refering to missions that had people on them not an activity that spends money for 50 years and might have people going to Mars at the end of the period. You know, much like the present day, even to the money spent.

          Well, the nature of research is that you have to spend the money BEFORE you find out if you're actually able to achieve the desired result. Good luck finding somebody willing to run a mission to Mars for an X-prize payable only after success.

          We could probably send 10 probes every launch window for a fraction of the cost of a manned mission. Surely they can't all have fatal flaws?

          And what would we do with them that would justify not having a manned presence? People keep forgetting how little we do with probes these days. It only looks like a lot because it's been 40 years since the last manned mission to another body in the Solar System.

          Also, it's worth noting that we're not really sending out a lot of probes. Sure, we're spending a lot of money. But we're just not getting much for the money.

          Well, if the science isn't worth it, then don't send the probes either. What would you do with people on mars?

          The fact is that going to Mars with robots or people is expensive. Doing it with people is just mind-bogglingly expensive. The only reason it makes sense to

          • by khallow (566160)

            What would you do with people on mars?

            Live there. Duh.

            • by Rich0 (548339)

              And what benefit does that provide to anybody? In particular, to those who aren't living there (though it isn't at all clear to me what benefits those living their obtain either).

              If I asked the US government to build me a house in the next town over for a few trillion dollars, I suspect I'd have to have a reason better than "so I can live there" if I wanted to gain any traction.

          • by khallow (566160)

            The only reason it makes sense to send people is if there is some objective to accomplish on Mars where sending people is more cost-effective than sending a probe. I can't really think of any scenario where that is the case.

            To elaborate on my previous remark, there's some portion of the population who is in favor of human colonization of space. That inherently requires humans at some point to do. It also requires a lot of knowledge about the environments and resources of the areas that we would attempt to colonize. Hence, there is a deep need for human-oriented space science if this group is to achieve its aims.

            Second, these are pretty well known goals. I doubt you've never heard of proposals to colonize Mars. There's a sc

            • by Rich0 (548339)

              So, right now I can't see why anybody would want to live on Mars. It is kind of like living in the middle of the Sahara, but less hospitable, and I don't see people signing up to live there on their own dime.

              If I did want to colonize mars, landing people there would be the LAST thing I did, and chances are it would be a century or two before getting to that. First give them someplace to live. You might be able to build a base on Mars, but that wouldn't give you anything you wouldn't get cheaper by just b

              • by khallow (566160)

                It is kind of like living in the middle of the Sahara, but less hospitable, and I don't see people signing up to live there on their own dime.

                I don't see you looking for such people either. But having said that, there's quite a few people living in the Sahara. Googling around, I see estimates of a few million (2-4 million) depending in large part on what you consider part of the Sahara. It doesn't have significant population density, but people do live there mostly on their own dime.

                If I did want to colonize mars, landing people there would be the LAST thing I did, and chances are it would be a century or two before getting to that.

                Why wait so long? The martian environment isn't going to change over that time to make life easier for us. Nor do I think we will develop technologies specific to Mar

                • by Rich0 (548339)

                  So, I've yet to hear a reason for colonizing Mars in the first place. Doing so is EXTREMELY expensive so it should be a means to an end, and not an end in itself.

                  About the only real reason I've heard for colonizing Mars is having people living outside the Earth in case something goes wrong with the Earth. However, that has no value at all unless these people can live completely independently of resupply from Earth, and if you want those people to live on Mars then there has to be some reason for them to b

                  • by khallow (566160)

                    About the only real reason I've heard for colonizing Mars is having people living outside the Earth in case something goes wrong with the Earth. However, that has no value at all unless these people can live completely independently of resupply from Earth, and if you want those people to live on Mars then there has to be some reason for them to be living there as opposed to someplace else, like in the middle of space.

                    This is one big reason why Mars is such a popular target for colonization. All the materials needed for Earth life and a technological civilization are present. So they can indeed live independently of Earth in a way that is much more difficult to accomplish on some other locations such as middle of space, the Moon, Venus, most asteroids, etc.

                    • by Rich0 (548339)

                      This is one big reason why Mars is such a popular target for colonization. All the materials needed for Earth life and a technological civilization are present.

                      Define materials needed for Earth life...

                      There isn't any O2 in the atmosphere, there isn't much of an atmosphere at all, though they do have dust storms so forget making your shelter out of aluminum foil like you can in space. Sure, there is lots of dirt, though that dirt contains no organic material needed to sustain plant life/etc.

                      It seems to me that in general the life support requirements on Mars aren't any better than what you'd need in the middle of space. You'd need to meticulously recycle everythi

                    • by khallow (566160)

                      Define materials needed for Earth life...

                      All the elements that animal or plant life uses.

                      There isn't any O2 in the atmosphere, there isn't much of an atmosphere at all, though they do have dust storms so forget making your shelter out of aluminum foil like you can in space. Sure, there is lots of dirt, though that dirt contains no organic material needed to sustain plant life/etc.

                      The atmosphere has CO2 and nitrogen which we can readily turn into plants and oxygen (there's your organic materials). There is some quantity of water and carbon dioxide underground. And we can make that shelter out of dirt or metals such as aluminum and steel which we can mine from either the dirt or meteorites (which are very plentiful on Mars).

                      It seems to me that in general the life support requirements on Mars aren't any better than what you'd need in the middle of space. You'd need to meticulously recycle everything, as there would be no renewal except from Earth resupply (which won't be available if the Earth is wiped out or whatever the doomsday scenario is - and for the biggest doomsday scenario of all (nuclear war) I'd rather be on the Earth where at least I can try to live in a cave than on a fragile space colony whose exact coordinates are well known to those firing the missiles).

                      Life support requirements aren't different on Earth either. We still need the same things here that we'd need on Ma

                    • by Rich0 (548339)

                      The atmosphere has CO2 and nitrogen which we can readily turn into plants and oxygen (there's your organic materials). There is some quantity of water and carbon dioxide underground. And we can make that shelter out of dirt or metals such as aluminum and steel which we can mine from either the dirt or meteorites (which are very plentiful on Mars).

                      Ah, so we just need to reduce CO2 and fix N2. If we could do that artificially for any practical amount of money we'd have fixed global warming and would be growing crops in the Sahara.

                      The only practical way to do those things right now is via plants/algae/etc. And, if you could get those to grow on Mars then all you need to do is seed the planet with them and it would basically terraform itself. If you could do that then it would be a place worth living on (well, assuming you could do something about th

                    • by khallow (566160)

                      If we could do that artificially for any practical amount of money we'd have fixed global warming and would be growing crops in the Sahara.

                      And we do. That is, our approach to global warming is IMHO near optimal (it is as fixed as we desire it to be) and we do grow crops in the Sahara.

                      My point was that the life support / engineering requirements are the same or even less in space than on Mars. So, why live on Mars as opposed to space? Mind you, I don't see the point in living in space either until we are far more advanced.

                      And my point was that the life support/engineering requirements are no different than they would be on Earth. Laws of physics don't change as you go from Earth to space.

                      Ah, you want to live on Mars, that place where anybody can stake a claim and be magically free from all the politics that happen on Earth. Never mind that you'd need one of those pesky governments to build your colony in the first place - I'm sure they'll be happy to let the colonists just do whatever they want to free of interference after spending a few trillion dollars putting them there. And, if you somehow strike out and build your own little hut in the middle of the dirt, I'm sure nobody will show up with a gun and try to take it from you.

                      You'd get further moving to Rhode Island and voting in Libertarians or something. If you want to be free of government interference the last thing you want to be doing is asking for a few trillion dollars in Federal funding to build a colony on Mars.

                      And why do you think it would cost that much or that a government would be needed? We aren't exactly standing still in technology development or manufacture capability here.

                      Instead, I'd wager th

                    • by Rich0 (548339)

                      And my point was that the life support/engineering requirements are no different than they would be on Earth. Laws of physics don't change as you go from Earth to space.

                      Sure, but the environmental conditions are different.

                      A rat can engineer suitable living conditions on Earth. I'd like to see one design a habitat for living on Mars. The required conditions are no different, but the lack of 1atm of 20% O2 everywhere, and water falling from the sky, and stuff you can eat literally lying all over the place sure is different.

                      In any case, if you're looking to privately fund a mission to Mars don't let me discourage you. As long as you're not asking me to pay for it and my el

  • So some people have said they have a duplicate drill here on earth. Can't they at least roughly simulate the same work that the Mars one is going to do, and see how much contamination happens, then compensate in the results? Totally out of my field, so I have no idea.

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